My coworkers and I study adult stem cells that live in the bone marrow. Some of these cells give rise to red and white blood cells and are called hematopoietic stem cells (HSCs). Others give rise to bone, cartilage, and fat and are called bone marrow stromal cells (BMSCs). We found that these different populations are connected to each other and can and do regulate each others' function. We study a variety of anaemia models to mimic possible scenarios that might occur in the humans. When we lose blood, we become anaemic, because we also lose the blood cells. Certain toxins (sometimes overdoses of medicine) will cause our red blood cells to dissolve in the circulation (it is called hemolysis) and these will need to be replaced very quickly, since they carry the oxygen. Finally, when the bone marrow gets suppressed (for instance following chemotherapy), we also need to make more new cells so that the number of circulating cells could keep up with the demand. We have been studying the relationship between cells in the bone marrow, called the bone marrow niche. This is the space where cells interact and regulate each others functions. We are trying to develop techniques to separate and study the red and white blood cells from the specialized bone marrow stromal cells that regulate their development, a process called hematopoiesis. We hope that by studying these interactions we can find new ways to control the proliferation of white and red blood cells.